Preheat the oven to 350°F. Lightly spray a 9-inch spring-form pan with nonstick cooking spray.
Place about half of the Oreos (about 18) in a gallon size zip-top bag. Crush the cookies using a rolling pin. Pour the crushed Oreos into a small bowl and mix with the melted butter. Pour the mixture evenly into the bottom of the spring-form pan and press firmly to create a crust.
In the bowl of a stand mixer (or with a bowl and hand mixer) combine the softened cream cheese, sugar, and vanilla until well combined. Add the eggs and mix well. Roughly break up the remaining cookies and add them to the mixture, reserving some to sprinkle on top. Gently fold the cookies in and pour the batter onto the crust. Lightly tap the pan on the counter to get out any air bubbles. Sprinkle with the remaining Oreos.
Bake for 40 to 50 minutes, or until the center in almost completely set. Cool and then refrigerate overnight to allow the cheesecake to firm up before serving (or at least 3 hours for those impatient folks). Drizzle with chocolate syrup and add a dollop of whipped cream, if desired.